WASHINGTON — The government’s climate change research is threatened by spending cuts that will reduce scientists’ observations from space and on the ground, a study says.

A major problem, the National Research Council said Thursday, is the program director’s lack of authority to organize spending and research among the 13 different agencies that study the impacts of climate.

Nonetheless, the report said, the U.S. Climate Change Research Program has made good progress “in documenting the climate changes of the past few decades and in unraveling the (human) influences on the observed climate changes.”

In contrast, the report said progress in combining research results and supporting decision making “has been inadequate.”

The climate research program is “an important initiative that has broadened our knowledge of climate change, needs to package more of that knowledge for policymakers from the national to local level, and place more emphasis on understanding how people will be affected by climate change and how they might react,” said committee chairman Veerabhadran Ramanathan, professor of atmospheric and climate sciences at University of California, San Diego.

The world has moved into an era when climate change is accepted as real, he said, and it is accepted that human activities are the major drivers for many of these changes.

But progress has been inadequate in determining how climate change will affect people, Ramanathan said in a briefing Thursday.

In its report the research council, an arm of the National Academy of Sciences, did not make recommendations on how to improve the program. That is expected to be included in a follow-up report next year.

The study expressed concern about delays, cutbacks and cancellations of programs that would maintain or add to climate change research.

“Knowledge of climate variability and change rests on consistent long-term observations that are broadly disseminated and archived for future generations of scientists,” the report said.

However, it said, several planned satellite sensors critical to the long-term data gathering have been canceled or seriously delayed. It cited cancellation of the Hydros mission to answer questions about the water cycle.

The Global Precipitation Measurement mission has been delayed, the report added, and it is unclear whether foreign initiatives can fill in.

“A major potential red light is the decline in observing capability,” Ramanathan said.

For example, he said, critical measuring instruments in space are expected to decline from more than 120 instruments last year to 80 by 2010.

In June, The Associated Press reported that the Bush administration was drastically scaling back efforts to measure global warming from space, even while the president was trying to convince the world the U.S. is ready to take the lead in reducing greenhouse gases.

The report noted that the Defense Department has decided to downsize the number of satellites intended to gather weather and climate data, replacing existing satellites as they come to the end of their useful lifetimes beginning in the next couple of years.

The reduced system of four satellites will now focus on weather forecasting. Most of the climate instruments needed to collect more precise data over long periods are being eliminated.

Instead, the Pentagon and two partners — the National Oceanic and Atmospheric Administration and NASA — will rely on European satellites for most of the climate data.

“Unfortunately, the recent loss of climate sensors … places the overall climate program in serious jeopardy,” NOAA and NASA scientists told the White House in the Dec. 11 report obtained by the AP.

In addition, the new National Research Council report said, surface-based data collection systems are either deteriorating, such as the Geological Survey’s streamflow monitoring, or are continually threatened with cutbacks, such as the Agriculture Department’s snowpack observing system.

The National Academy of Sciences is an independent organization chartered by Congress to advise the government on scientific issues.